Pressure gauge fitting

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flips

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JOHNSTON 135 HP 1975<br />I what to re-install my existing water pressure gauge to this motor and also a pee hole.Have looked at many posts,but are not 100%<br />sure on the point to tap it.On no 1 side of the block their is two prongs in line - above top one ,there is a<br />small flat spot, that looks like a little circle.<br />this is where i think you tap looking at other posts.<br />Thankyou in advance for your help
 
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Dhadley

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Re: Pressure gauge fitting

Thats an excellent place. That will also vent any air trapped in the block too. Dont drill too deep, the water jacket isnt that deep there. The best way, on your first time, is to remove the head so you can see what your drilling into. Besides, its probably been a while since the deflectors were changed. <br /><br />The elbow goes there and the line runs down and thru the pan for your overboard indicator. You can "T" into that for the pressure gauge.<br /><br />Good luck!
 
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flips

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Re: Pressure gauge fitting

Thanks Dhadley<br />Thats what i wanted to here,like to 100% sure to avoid damage.<br />Deflectors are behind the exhaust cover looking at other models.My book does not have a drawing of my model so am not sure whats behind the door ? thanks again.
 
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lawyertob

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Re: Pressure gauge fitting

Originally posted by Dhadley:<br /> Thats an excellent place. That will also vent any air trapped in the block too. Dont drill too deep, the water jacket isnt that deep there. The best way, on your first time, is to remove the head so you can see what your drilling into. Besides, its probably been a while since the deflectors were changed. <br /><br />The elbow goes there and the line runs down and thru the pan for your overboard indicator. You can "T" into that for the pressure gauge.<br /><br />Good luck!
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Dhadley,<br /> Is it better to tap in there or through the Exhaust cover. I asked pretty much the same question last week and was told to tap into the square at the bottom of the exhaust cover. I have a 1975 115 HP and I think it is exactly the same engine with different gearing. My post was a week or so ago, if you want to look it up.<br /><br />Thanks,<br />Joe
 
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Dhadley

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Re: Pressure gauge fitting

You can tap into the exhaust cover. We usually add the vent at the top to eliminate the trapped air anyway. Then just "T" into that line. Either way works. <br /><br />The gear ratio is the same on the 115 and 135, BTW. <br /><br />Flips -- the ceflectors are small rubber pieces of hose in the water passages. Once you remove the heads you'll see them. Two on each side.
 
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lawyertob

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Re: Pressure gauge fitting

Originally posted by Dhadley:<br /> You can tap into the exhaust cover. We usually add the vent at the top to eliminate the trapped air anyway. Then just "T" into that line. Either way works. <br /><br />The gear ratio is the same on the 115 and 135, BTW. <br /><br />
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Dhadley,<br /><br /> Thanks for the reply. I think I like this method better, both for the venting and to have less tubing. Now I just have to go look and see if I can locate that spot.<br /><br /> Also, I don't mean to argue, but the reason I jumped into this thread is because my owners manual says that the 115 and 135 have identical bore, stroke, and displacement and that the 115 has 13:26 gearing while the 135 has 13:25 gearing. Oh well, it doesn't matter to me as long as I know there might be a better place to do my gauge/tell-tale tap<br /><br />Thanks,<br />Joe
 
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Dhadley

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Re: Pressure gauge fitting

Yes, your correct. The ratio is different but its so close that its really hard to tell any difference on most hulls. Thats why they eventually went to one ratio for that style motor.
 
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flips

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Re: Pressure gauge fitting

Jobs done,working great thanks for the info <br />Dhadley. :D
 
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lawyertob

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Re: Pressure gauge fitting

flips,<br /><br />Could you take a pic of where your fitting went and post it? I have looked on my 115 and don't find any prongs anywhere. I do have a fairly flat area about 3 inches on a side on the top of the block above #1 cylinder...like right around the curve from the bypass cover, but mo prongs and no circle...I guess the castings are different.<br /><br />I know where to tap into the exhaust cover, but I would rather do it on top for venting purposes.<br /><br />Thanks,<br />Joe
 
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flips

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Re: Pressure gauge fitting

Joe send your email address and i will send pics.<br />Cant work how to get them on forum yet.<br />.flips
 
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Dhadley

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Re: Pressure gauge fitting

Glad to hear it worked out!<br /><br />Thanks for the update!!
 
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lawyertob

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Re: Pressure gauge fitting

Originally posted by flips:<br /> Joe send your email address and i will send pics.<br />Cant work how to get them on forum yet.<br />.flips
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flips,<br /><br />My address is in my profile or you can just send it to joeglastront186(at)aol(dot)com.<br /><br />Thanks,<br />Joe
 
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flips

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Re: Pressure gauge fitting

Joe sent email hope it works.<br />Thanks again Dhadley for your help.
 
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